Concealed-type fire protection sprinklers, which discharge a fire fighting fluid such as a water, gas or other chemical agent, can be designed to protect a variety of occupancies, both commercial and residential. Generally, the concealed nature of these sprinklers obscures the internal components of the sprinkler from view for at least aesthetic reasons depending upon the given installation. In addition or in the alternative, the concealing structure of the concealed-type sprinkler can protect the internal components from either tampering or accidental impact. Regardless of the purpose of the concealing structure of the sprinkler, it is critical that the concealing structure not interfere with the thermal responsiveness or operation of the sprinkler. This is particularly true in which the concealed-type sprinkler must satisfy a response time requirement or standard in order to be listed under any one of the applicable installation/sprinkler standards for a particular occupancy such as, for example, protection of a residential occupancy.